Abstract: Fiber optic grating sensor demodulation systems are described that offer high speed and multiplexing options for both single and multiple parameter fiber optic grating sensors. To attain very high speeds for single parameter fiber grating sensors ratio techniques are used that allow a series of sensors to be placed in a single fiber while retaining high speed capability. These methods can be extended to multiparameter fiber grating sensors. Optimization of speeds can be obtained by minimizing the number of spectral peaks that must be processed and it is shown that two or three spectral peak measurements may in specific multiparameter applications offer comparable or better performance than processing four spectral peaks. Combining the ratio methods with minimization of peak measurements allows very high speed measurement of such important environmental effects as transverse strain and pressure.

Abstract: A fiber grating corrosion sensor system which includes fiber grating corrosion and/or chemical sensors formed by writing one or more fiber gratings that are transverse load sensitive so that when corrosion occurs to a transverse stress applying sleeve there over, the transverse loading is relieved. The spectral signals from the fiber grating sensors change with variations in transverse strain providing a measurement of the degree of corrosion or change in chemical content.